After losing all four matches in their maiden Super Rugby season so far, the woes are piling up for the Sunwolves as they are set to lose key player Tusi Pisi when the current campaign ends.

The 33-year-old Samoan fly-half announced on Thursday that he will leave the Japanese team and join English second-tier club Bristol Rugby on a two-year deal.

He said in a statement on the club's website: "I'm delighted to be joining Bristol and look forward to playing club rugby in England for the first time.

"I have spoken to the Samoan contingent at Bristol and have heard great things so I'm excited to get involved and help the team."

Pisi will join his compatriots David Lemi, Jack Lam and Anthony Perenise at Bristol. He has 28 international caps and played in all four of Samoa's matches at last year's Rugby World Cup in England.

A former Hurricanes and Crusaders player, Pisi has recorded 40 points - half the total scored by the Sunwolves in their opening four matches this season.

Bristol's director of rugby Andy Robinson said: "Tusi is Samoa's first-choice fly-half and a respected leader. He's developed a reputation as an intelligent, level-headed fly-half with a strong kicking game."

The Sunwolves are one of two new entrants along with Argentinian side Jaguares to join the league this year. The Japanese side hope to get their first Super Rugby win when they take on struggling South African team Kings today in Port Elizabeth.

The Kings are the only outfit who have yet to pick up a point.